PURPOSE: Reports on intraocular pressure (IOP) changes at high altitudes have provided inconsistent and even conflicting RESULTS: The purpose of this study was to investigate the effect of very high altitude and different ascent profiles on IOP in relation to simultaneously occurring ophthalmic and systemic changes in a prospective study. METHODS: This prospective study involved 25 healthy mountaineers who were randomly assigned to two different ascent profiles during a medical research expedition to Mt. Muztagh Ata (7,546 m/24,751 ft). Group 1 was allotted a shorter acclimatization time before ascent than was group 2. Besides IOP, oxygen saturation (SaO(2)), acute mountain sickness symptoms (AMS-c score), and optic disc appearance were assessed. Examinations were performed at 490 m/1,607 ft, 4,497 m/14,750 ft, 5,533 m/18,148 ft, and 6,265 m/20,549 ft above sea level. RESULTS: Intraocular pressure in both groups showed small but statistically significant changes: an increase during ascent from 490 m/1,607 ft to 5,533 m/18,148 ft and then a continuous decrease during further ascent to 6,265 m/20,549 ft and on descent to 4,497 m/14,750 ft and to 490 m. Differences between groups were not significant. Multiple regression analysis (IOP-dependent variable) revealed a significant partial correlation coefficient of beta = -0.25 (P = 0.01) for SaO(2) and beta = -0.23 (P = 0.02) for acclimatization time. DISCUSSION: Hypobaric hypoxia at very high altitude leads to small but statistically significant changes in IOP that are modulated by systemic oxygen saturation. Climbs to very high altitudes seem to be safe with regard to intraocular pressure changes.
RCT Entities:
PURPOSE: Reports on intraocular pressure (IOP) changes at high altitudes have provided inconsistent and even conflicting RESULTS: The purpose of this study was to investigate the effect of very high altitude and different ascent profiles on IOP in relation to simultaneously occurring ophthalmic and systemic changes in a prospective study. METHODS: This prospective study involved 25 healthy mountaineers who were randomly assigned to two different ascent profiles during a medical research expedition to Mt. Muztagh Ata (7,546 m/24,751 ft). Group 1 was allotted a shorter acclimatization time before ascent than was group 2. Besides IOP, oxygen saturation (SaO(2)), acute mountain sickness symptoms (AMS-c score), and optic disc appearance were assessed. Examinations were performed at 490 m/1,607 ft, 4,497 m/14,750 ft, 5,533 m/18,148 ft, and 6,265 m/20,549 ft above sea level. RESULTS: Intraocular pressure in both groups showed small but statistically significant changes: an increase during ascent from 490 m/1,607 ft to 5,533 m/18,148 ft and then a continuous decrease during further ascent to 6,265 m/20,549 ft and on descent to 4,497 m/14,750 ft and to 490 m. Differences between groups were not significant. Multiple regression analysis (IOP-dependent variable) revealed a significant partial correlation coefficient of beta = -0.25 (P = 0.01) for SaO(2) and beta = -0.23 (P = 0.02) for acclimatization time. DISCUSSION: Hypobaric hypoxia at very high altitude leads to small but statistically significant changes in IOP that are modulated by systemic oxygen saturation. Climbs to very high altitudes seem to be safe with regard to intraocular pressure changes.
Authors: Daniel Barthelmes; Martina M Bosch; Tobias M Merz; Benno L Petrig; Frederic Truffer; Konrad E Bloch; Timothy A Holmes; Philippe Cattin; Urs Hefti; Miriam Sellner; Florian K P Sutter; Marco Maggiorini; Klara Landau Journal: PLoS One Date: 2011-02-17 Impact factor: 3.240
Authors: Gabriel Willmann; M Dominik Fischer; Andreas Schatz; Kai Schommer; Andre Messias; Eberhart Zrenner; Karl U Bartz-Schmidt; Florian Gekeler Journal: PLoS One Date: 2011-11-01 Impact factor: 3.240
Authors: M Dominik Fischer; Gabriel Willmann; Andreas Schatz; Kai Schommer; Ahmad Zhour; Eberhart Zrenner; Karl U Bartz-Schmidt; Florian Gekeler Journal: PLoS One Date: 2012-04-30 Impact factor: 3.240
Authors: Matthew H Stahl; Alexander Kumar; Robert Lambert; Michael Stroud; David Macleod; Andrew Bastawrous; Tunde Peto; Matthew J Burton Journal: BMC Ophthalmol Date: 2018-06-25 Impact factor: 2.209